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FE Analysis and Experiments of Milli-fart forming Using Grain and Grain Boundary Element

입자요소를 이용한 미세 성형 부품의 유한요소 해석 및 실험

  • 구태완 (부산대학교 항공우주공학과) ;
  • 강범수 (부산대학교 항공우주공학과)
  • Published : 2003.01.01

Abstract

The recent trend towards miniaturization causes an increased demand for parts with very small dimensions. Milli-structure components are classified as a component group whose size is between macro- and micro-scale. The manufacturing process of these components of thin sheet metal forming has a microscopic properties in addition to a typical phenomenon of bulk deformation because of the forming size. Also, the material properties and the deformation behavior change with miniaturization, which means that, a coarse grained materials show a higher resistance against deformation, when the grain size is in the range of the sheet thickness. In this study, a new numerical approach is proposed to simulate intergranular milli-structure in forming by the finite element method. The grain element and grain boundary element are introduced to simulate the milli-structure in the bending. The grain element is used to analyze the deformation of individual grain while the grain boundary element is for the investigation on the movement of the grain boundary. Also, the result of the finite element analysis is confirmed by a series of milli-sized forming experiments.

Keywords

Milli-Component;Grain Element;Grain Boundary Element;FEM;Bending Process

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